Gravity-Fed Toilets
Updated February 20, 2026
The most common residential toilet type, using the natural force of gravity to flush waste. Reliable, quiet, and easy to maintain with widely available replacement parts.
Overview
Gravity-fed toilets are the standard type in most homes. Water drops from the tank into the bowl by gravity, creating the flush force. Simple, reliable, quiet, and easy to repair. No special water pressure required -- they work on any system. The siphon action pulls waste down and out. Available in round and elongated bowl shapes, standard and comfort height, one-piece and two-piece. If you are replacing a toilet and have no special requirements, a gravity-fed toilet is the default choice.
Pros & Cons
- Affordable
- Quiet operation
- Easy to repair
- Widely available parts
- Less powerful flush than pressure-assisted
- May require double flushing
Key Features
- Uses gravity from the elevated tank to create flush force -- no pump or special pressure needed
- Quietest flush type -- no pressure-assisted noise
- Simple internal mechanism: fill valve, flush valve, flapper, and handle
- Easy and inexpensive to repair -- parts are universal and widely available
- Available in 1.28 GPF (WaterSense) and 1.6 GPF models
Sizing & Selection
12-inch rough-in is standard (95%% of homes). Measure from the wall to the closet bolt center. Round bowls fit tight spaces (extends 25-27 inches from wall). Elongated bowls are more comfortable (extends 28-30 inches). Comfort height (17-19 inch seat height) is ADA-compliant and easier for adults. Standard height is 15 inches.
Installation
Standard toilet installation: set wax ring, lower onto flange bolts, tighten alternately, connect supply line, test. Two-piece: bolt the tank to the bowl first, then set. One-piece: heavier but simpler -- one unit sets on the flange. Level with shims if the floor is uneven. Caulk the base (leave back open for leak detection).
Maintenance
- Replace the flapper every 3-5 years -- the most common maintenance item.
- Adjust the fill valve if the water level is too high or too low.
- Clean under the rim with a brush and vinegar to keep flush holes clear.
- Tighten the tank-to-bowl bolts if you notice water between the tank and bowl. Replace the gasket if tightening does not stop it.
Buying Tips
- TOTO Drake is the gold standard for gravity-fed performance. Excellent flush, reasonable price (-400).
- Kohler Highline and American Standard Champion are also top performers.
- MaP (Maximum Performance) testing rates flush performance. Look for models rated 800+ grams -- these clear waste in a single flush consistently.
- Comfort height is worth the upgrade for adults. Standard height is fine for bathrooms primarily used by children.
- Slow-close seats prevent slamming and are worth the -20 premium. Many toilets now include them.